Reversing valves



April 10, 1956 w. D. LEONARD 2,741,264

REVERSING VALVES Filed Dec. 5, 1951 William DLeonard.

3nvenfor (Ittornegs United States Patent REVERSING VALVES William D.Leonard, York, 'Pa., assignor to York Corporation, York, Pa., acorporation'of Delaware Application December 5, 1951, Serial N 259,946

1 Claim. (Cl. 137-6255) Heat pumps of the reversible type can be usedinterchangeably for summer cooling and for winter heating of enclosedspaces.

The availability of a single piece of apparatus for two independentseasonal services is architecturally and economically attractive. Whenelectric current must be used for heating, and provided outdoortemperatures are not unduly low, the high performance factor of the heatpump makes it more economical than a resistance heater.

Since it is usually not conveniently practicable to reverse the unitbodily the commercial trend is toward use of two heat exchangers eitherof which may perform the functions of an evaporator while the otherperforms those of a condenser. These exchangers must be interchangeablyconnected with the compressor by a reversing valve and the troublesomefactor in the art is this valve.

It is to the provision of a satisfactory reversing valve that theinvention is directed. A valve of this type has two functionalpositions, in each of which it must form two tight seals against thepressure differential between compressor suction and discharge. Volatilerefrigerants commonly impair non-metallic substances so metals must beused even for sealing surfaces. The valve cannot readily be inspected,and leaks internal to the system, and great enough to cause seriousenergy losses, are not readily observable. Hence precise constructionand reliably maintained performance over a long life is needed. Leakagefrom the system cannot be tolerated.

A valve meeting the stated requirements and capable of manufacture atreasonable cost is shown in the accompanying drawing in which the singlefigure is a view in axial section of the complete valve. Portions of itsconnections are shown.

It is characteristic of the invention that two flexible double-beatvalves are mounted on a single stem and each valve seats selectively onone or the other of two opposed parallel seats. While the idealcondition would be offered by seats which are truly parallel, preciselyspaced and accurately centered on the axis of the valve stem, one of thevaluable attributes of the flexible metal disc valves is that they willaccommodate themselves without impairment of function to minorinaccuracies in seat location and so permit the use of commercialtolerances in the manufacture of the valve body. To permit attainment ofreasonable accuracy at moderate cost the valve body is constructed inthree separately machined parts so contrived as to favor accurateassembly.

The middle portion 1 of the body is in the form of a generallycylindrical sleeve having a cross partition 2 at its middle, bored toafford an axial passage 3 which terminates in outward presented seatrims 4 and 5. A side passage 6 leads to passage 3 between seats 4 and 5,and receives a connection 7 to one of the heat exchangers (not shown)which is converted by the valve between evaporator and condenserfunctions. Two side passages 8 and 9 receive connections 11 and 12 oneconnected to the discharge and the other to the suction of thecompressor (not shown).

The passages 8 and 9 enter chambers 13 and 14 in the ends of portion 1between the seat 4 or 5 and the opposed seat. I

The ends of portion 1 are counterbored to shoulders 15 and eachcounterbore confines circumferentially and its shoulder 15 definitelypositions a corresponding end portion 16 or 17 as the case may be.

Portion 16 has a ported end which terminates in a seat rim 18 andportion 17 has a similar ported end which terminates in seat rim 19. Theseats 4 and 18 are opposed to each other in chamber 14 and the seats 5and 19 are opposed to each other in chamber 13. All seats are centeredwitha good degree of accuracy on the axis of the valve stem hereinafterdescribed and said axis is normal to each, at least within goodcommercial tolerances.

Throughout the drawing, fused metal joints (whether they be brazed,soldered or welded) are indicated by the numeral 20 and need not befurther described.

The outer end of portion 17 is closed by a head 21 with a blind guideway 22 and spline 23 intended to guide the lower end of valve stem 24and prevent it from rotating. The head 21 is mounted against a shoulderin a counterbore. The metal of the portion 17 is headed over and weldedas indicated.

The outer end of portion 16 is closed by a head 25, sealed in place inthe manner already described as to head 21. It has an extension with athreaded axial bore 26 in which it mounted the threaded actuating stem27. This may be turned by handwheel 28. An oil port is shown at 29.

The lower end of stem 27, within threaded portion 26, is bored andthreaded as indicated at 31 to engage the upper threaded end of stem 24.The threads at 26 and 31 are difierentiated so that turning of stem 27will cause valve stem 24 to shift axially. If one thread is right andthe other left handed, rapid motion of the valve stem may be had.

A metal disc 32 is sealed to a shoulder on stem 24, and corrugated metalbellows 33 connect disc 32 and head 25, affording a reliable sealwithout the use of packing around the stem 24.

The upper double-beat valve 34, which seats alternately against seats 4and 18 is a flexible annulus of elastic sheet metal. Laminationincreases initial flexibility. Two laminae are shown, since two areordinarily suflicient. The lower double-beat valve is really twoflexible annuli 35 and 36 (each shown as comprising two laminae ofelastic sheet metal) separated by a double convex lenticular spacer 37.This is used to'limit only the extreme flexure of the valve annuli, andconsequently is essentially rigid. The upper valve seats against ashoulder 38 on stem 24. Between annuli 34 and 35 is a spacing sleeve 39and below annuli 36 is a second spacing sleeve 41. The parts are held inassembled relation by nut 42 and check nut 43 threaded upon the lowerend of stem 24.

The chambers within portions 16 and 17 freely communicate with eachother through connection 44 and with the other heat exchanger (notshown) through connection 45.

While definite connections have been suggested, valves of this type canbe variously connected. The invention resides in the valve structure,and this may be used for any purpose to which it is adaptable.

So far as is material, the valve in its lower position (as shown) closesthe passages controlled by seats 4 and 19 and opens those controlled byseats 5 and 18. In the upper position the passages controlled by 5 and18 are closed and those controlled by 4 and 19 are open.

The valve has the advantage of all metal construction,

ama ed:

and tight seals afiorded by adequately loaded elastic metal discs.

What is claimed is:

In a four-way valve, the combination of a valve hous; inghavingafirst-pair" of opposed coaxial annular valve seats, and having coaxialtherewith'asecondpair'of'rnore widely spaced opposed coaxiflannular'valve; seats, said sea-tsbeing interposed betweenfiowconnections; a valve stem; means for shifting said stem in a pathcoincident with the axes of the; stem and seat; saidstern extendingthroughsaidvalve seatsalhof-"Which are substantially normaltosaidaxesyafirst fiexibi'e double heat'valve comprising a flat annulus of" elasticsheet metal positioned betweenthe seats-of the firstpair, adapted toseat selectively against said, seats; as the stem is' shifted, and attached to the stem in an annular area; materially smaller than theopenings through the firstrpair of valve seats; a

second" double-beat valve comprising; two fiat annulij of elastic;sheet-metal; separatedbya double convex ljenticular spacer, andpositioned between the seats of the second pair, the annuli beingadapted'to seat selectively against the seats of the second pair andbeing clamped'to: the

spacer in annular areas smaller than the openings through thesecond pairof" seats; the spacer being of-- such outside diameter relatively to theopenings through the seats of the second pair and of such thicknessadjacent its center relatively to the difierential between the spacingsof the seats of the two pairs, as to arrest motion of the stern in eachdirection after both doublerbeat valves are seated.

References-.Eited'imthe file-,0? this patent UNITED, STATES, PATENTS860,258 Slick July 1 6', 1907 1,235,338 Lernp. ,July 31,1917 1,478,815Blauvelt Dec. 15, 1923 1,575,771 Mar. 9, 1926 1,802,093 Slagel Apr. 21,1931 1,855,354 Kennedy -QApr. 26, 1932 1,921,092 Newton Aug. 8, 19332,138,513 1 Rossman N'ov;29, 1938 2,188,836 Goodwin Ian. 30'; 19402,640,494 Kounovsky ,V Ji1ne 2,1953 2,703,106 Borgerd" Mar. 1, 19,55

